Adjustable arm for multispindle drills



W. F. BOCKHOFF.

ADJUSTABLE ARM FOR MULTISPINDLE DRILLS.

APPLICATION FILED FEB. 20. I918.

Patented Nov. 23, 1920.

F l'll I II avwemboz W/Ham @oc Khoff,

WILLIAM F. BOCKHOFF, 0F RICHMOIQ'D, INDIA PATENT OFFICE.

NA, ASSIGNOR TO NATIONAL AUTO- MATIC TOOL COMPANY, or RICHMOND, INDIANA, A oonrom OFINDIANA ADJUSTABLE ARM FOR MULTISPINDLE DRILLS.

T 0 wZZ wh0m it may concern:

Be it known that I, WILLIAM F. BooK- Horr, a citizen of the United States resid-' produced by a single feeding action of the work-supporting table or the main head carrying all the spindles.

The space within which vertical adjust ment may be accomplished and within which the adjusting mechanism may be adjusted, is comparatively limited and yet the adjusting mechanism must be repeatedly manipulated during any working period.

The object of my present invention is, therefore, to produce an efficient adjusting mechanism, by means of which the vertical position of a drill-carrying spindle may be attained,,of such character as to be eflicient at all times and readily manipulated.

The accompanying drawings illustrate my invention. Figure 1 is a side elevation, in partial vertical section, of an apparatus embodying my invention; Fig, 2 is a plan.

. In the drawings, 10 indicates the spindlecarrying arm which is supported on the usual support 11, by means of the clamping bolt 12. This arm 10 comprises a pair of parallel sides, as indicated in Fig. 2, between which the bolt 12 may extend, and a somewhat vertically extended head 13. which comprises a vertical cross plate 14 bridging the space between the two side pieces. The forward or end face of this plate 14 forms a support and guide for the vertically adjustable spindle head 15 which carries a pair of rearwardly projecting threaded pins 16, 16 which pass through vertical slots 17 17 formed through plate 14. On the threaded portion of each screw 16 is a clamping nut 18. The rear face of plate 14 is smooth and preferably parallel with the forward face and slidably mounted upon this face be- Specification of Letters Patent.

tween the two bolts 16, is a friction clamping shoe 19 adapted to be engaged by lever 20, the ends of which are bifurcated and straddled over the bolts 16 beneath the nuts 18. The ad acent faces ofshoe l9 and lever 20 are so formed that the lever/20 may rock upon. the shoe 19 and, in the form shown in the drawlngs, the shoe is shown as tapered toward each end from the middle so as to form a central peak 21 upon which the lever 20 may rock.

These two parts 19 and 20 may be conveniently formed ofmaterial which may be hardened sothat there will be no crushin of contacting points under pressure exerted by the nuts 18. The forward or friction face of shoe 19 is preferably smooth so as to-slldefreely upon the rear face of plate 14 but it Wlll be readily understood that these two contacting faces may be roughened or serrated, if desired.

In assembling the parts, the upper one of nuts 18 will be set to desired position where 1t forms an adequate abutment for the upper end of lever 20. By tightening the lower nut 18, lever 20 will exert a uniform pressure upon shoe 19 and a consequent unlform pull upon both of the bolts 16 so as to firmly and uniformly clamp the spindle head 15 upon the forward face of plate 14. A loosening of-the lower nut 18 only will serve to free the spindle head 15 so that it may be readily vertically adjusted.

By providing the shoe 19, I distribute, over a considerable area, the clamping pressure exerted by lever 20 so that the rear face of plate 14 is not marred and, consequently,

so thatthere is no tendency toward production of valleys in the rear face of plate 14, and a consequent interference with ready and accurate adjustment. i

I claim as my invention:

1. The combination, with a member having a receiving plate, of an adjustable member slidably mounted on said plate, two bolts carried by said spindle and projecting through the plate, a clamping nut mounted on each bolt, a friction shoe between: the bolts and movable therewith and arranged to engage the plate, and a lever Patented Nov. 23, 1920. Application filed February 20, 1918. Serial No. 218,346.

.ing a receiving plate, of a headslidably lever having a rocking engagement with the friction shoe, an abutment carried by the adjustable head and engaging one end of said lever, and an adjustable abutment carried by the adjustable head. and arranged to efifage the opposite end of said lever vari- 1 1 1 witness whereof, I WILLIAM F. Boon- HOFF have hereunto set m mond, Indiana, this 18th ay' of February,

hand at Rich- A. D., one thousand nine hundred and eighteen.

WILLIAM F. BOCKHOFF. 

